August 11, 2011

Newborn Oxygen Screening Test

(Ivanhoe Newswire) -- A quick, non-invasive test that measures blood oxygen levels in newborns detects more cases of life-threatening congenital heart defects than current standard approaches and should be adopted into the routine assessment of all newborns before discharge from hospital, according to this study.

Congenital heart defects are one of the leading causes of deaths in infants in the developed world. Current screening techniques involving a mid-trimester ultrasound scan and a routine physical examination shortly after birth fail to detect many life threatening heart abnormalities. As a result, a substantial number of babies leave hospital undiagnosed which can lead to higher rates of complications and even death.

In the largest UK pulse oximetry test accuracy study to date, Andrew Ewer from University of Birmingham and Birmingham Women's Hospital, Birmingham, UK and colleagues prospectively assessed the ability of the test to detect critical congenital heart disease (causing death or requiring invasive intervention before 28 days) or major congenital heart disease (causing death or requiring invasive intervention before 12 months of age).

Between February 2008 and January 2009, over 20 000 apparently healthy newborn babies from six maternity units across the UK were screened with pulse oximetry before discharge from hospital and followed up to 12 months of age.

The authors found that pulse oximetry detected 75% of critical cases and 49% of all major congenital heart defects. The detection rate of pulse oximetry, after excluding 35 cases of suspected congenital heart defects following antenatal ultrasound, was 58% for critical cases and 28% for all major cases.

When pulse oximetry was combined with routine ultrasound and newborn physical examination, it improved the detection of critical congenital heart defects to 92%, and no babies died from undiagnosed heart disease.
Pulse oximetry had a false positive rate of 0.8% (169 babies). However, six of these babies had significant heart defects, and a further 40 babies had additional problems (respiratory disorders and infections) that required urgent medical intervention.

"Pulse oximetry is a safe, non-invasive, feasible, and reasonably accurate test, which has sensitivity that is better than that of antenatal screening and clinical examination"¦It adds value to existing screening and is likely to be useful for identification of cases of critical congenital heart defects that would otherwise go undetected. The detection of other diseases"¦is an additional advantage," the authors were quoted as saying.

They conclude: "The results of this study enhance the strong evidence that indicates the potential benefits of predischarge pulse oximetry screening as a routine procedure."

SOURCE: Lancet, published online August 11, 2011